In recent years, for a read/write apparatus such as a magnetic disk apparatus, which writes data, high-density data writing is required. By increasing a track density on a magnetic disk, data can be written at a high density.
However, by increasing the track density, a phenomenon in which data written as magnetic information in a neighborhood track of that on which data is written is not correctly read (ATI: Adjacent Track Interference) often occurs.
Hence, when the ATI occurred, data is read from the magnetic disk, and the read data is written again on the magnetic disk, thus refreshing the data. By executing a refresh, the data can be recovered.
However, when a refresh is required to be executed at the time of execution of a normal read/write, the refresh interrupts the normal read/write. Also, redundant unwanted processing is executed at the time of the refresh and normal read/write. For this reason, for example, a time required for the normal read/write is prolonged, thus lowering the performance of the magnetic disk apparatus.